The development of the EDVAC computer system of 1948 is often cited as the beginning of the computer era. Since that time, computer systems have evolved into extremely sophisticated devices, and computer systems may be found in many different settings. Computer systems typically include a combination of hardware components (such as semiconductors, integrated circuits, programmable logic devices, programmable gate arrays, power supplies, electronic card assemblies, sheet metal, cables, and connectors) and software, also known as computer programs.
During the course of performing operations, computer programs may encounter errors, failures, or other abnormal conditions, which cause the computer program to generate an exception. For example, data may be temporarily unavailable or locked for use by another program, a computer system or network may be slow or unavailable due to a high load, or a file may not be found.
Some exceptions may be expected while others are unexpected, the success or failure of an operation may be subjective, an exception that one program considers successful another program may consider a failure, and the program that generates an exception may not be the root of the problem; instead, the problem may be in the way that the program was invoked. For example, a utility that opens files may report two different conditions: that the file was found and opened, or the file was not found. Both conditions might not be considered failures to the open utility because it performed its job correctly. Similarly, the program that invokes the open utility may simply create the file if it does not exist, so the invoking program also does not consider the file-not-found condition to be a failure. But, another program that invokes the open utility might interpret the file-not-found condition to mean that important data has been lost, so the operation cannot continue. Thus, merely knowing that an open utility reported a file-not-found exception is not enough information to determine the source of the problem, or even if a problem exists at all.
Because some exceptions may indicate problems that need to be fixed while others do not, and the program that generates the exception may not be the source of the problem, if a problem even exists at all, users need a better way to track exceptions and to understand the source and cause of exceptions.